CPU reservations and time constraints: efficient, predictable scheduling of independent activities
Proceedings of the sixteenth ACM symposium on Operating systems principles
A comparison of Windows driver model latency performance on Windows NT and Windows 98
OSDI '99 Proceedings of the third symposium on Operating systems design and implementation
Scheduling Algorithms for Multiprogramming in a Hard-Real-Time Environment
Journal of the ACM (JACM)
An overview of the Rialto real-time architecture
EW 7 Proceedings of the 7th workshop on ACM SIGOPS European workshop: Systems support for worldwide applications
The Modem Technical Guide
Inside Microsoft Windows 2000
SVR4UNIX Scheduler Unacceptable for Multimedia Applications
NOSSDAV '93 Proceedings of the 4th International Workshop on Network and Operating System Support for Digital Audio and Video
HOTOS '99 Proceedings of the The Seventh Workshop on Hot Topics in Operating Systems
CPU reservations and time constraints: implementation experience on windows NT
WINSYM'99 Proceedings of the 3rd conference on USENIX Windows NT Symposium - Volume 3
IEEE Journal on Selected Areas in Communications
Inferring Scheduling Behavior with Hourglass
Proceedings of the FREENIX Track: 2002 USENIX Annual Technical Conference
Supporting time-sensitive applications on a commodity OS
ACM SIGOPS Operating Systems Review - OSDI '02: Proceedings of the 5th symposium on Operating systems design and implementation
A case for virtual channel processors
NICELI '03 Proceedings of the ACM SIGCOMM workshop on Network-I/O convergence: experience, lessons, implications
Supporting time-sensitive applications on a commodity OS
OSDI '02 Proceedings of the 5th symposium on Operating systems design and implementationCopyright restrictions prevent ACM from being able to make the PDFs for this conference available for downloading
Hi-index | 0.00 |
Soft Modems use the main processor to execute modem functions traditionally performed by hardware on the modem card. To function correctly, soft modems require that ongoing signal processing computations be performed on the host CPU in a timely manner. Thus, signal processing is a commonly occurring background real-time application---one running on systems that were not designed to support predictable real-time execution. This paper presents a detailed study of the performance characteristics and resource requirements of a popular soft modem. Understanding these requirements should inform the efforts of those designing and building operating systems needing to support soft modems. Furthermore, we believe that the conclusions of this study also apply to other existing and upcoming soft devices, such as soft Digital Subscriber Line (DSL) cards. We conclude that (1) signal processing in an interrupt handler is not only unnecessary but also detrimental to the predictability of other computations in the system and (2) a real-time scheduler can provide predictability for the soft modem while minimizing its impact on other computations in the system.